Vchiq errors when plug in HDMI cable

[Aiexis]

Hello
as said in a previous closed issue #253 I get some odds messages with dmesg when a plug the hdmi cable:

[ 5374.930044] WARNING: CPU: 0 PID: 9633 at drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:2501 vchiq_release_internal+0xbc/0x254
[ 5374.932348] Modules linked in: brcmfmac brcmutil cfg80211 rfkill bcm2835_gpiomem uio_pdrv_genirq fixed uio snd_bcm2835 snd_pcm snd_timer snd ipv6
[ 5374.934879] CPU: 0 PID: 9633 Comm: HTV Notify Not tainted 4.9.35-v7+ #1014
[ 5374.937262] Hardware name: BCM2835
[ 5374.939660] [<8010fb3c>] (unwind_backtrace) from [<8010c058>] (show_stack+0x20/0x24)
[ 5374.942118] [<8010c058>] (show_stack) from [<80455880>] (dump_stack+0xd4/0x118)
[ 5374.944556] [<80455880>] (dump_stack) from [<8011d344>] (__warn+0xf8/0x110)
[ 5374.946957] [<8011d344>] (__warn) from [<8011d42c>] (warn_slowpath_null+0x30/0x38)
[ 5374.949463] [<8011d42c>] (warn_slowpath_null) from [<80600010>] (vchiq_release_internal+0xbc/0x254)
[ 5374.952029] [<80600010>] (vchiq_release_internal) from [<80600cc4>] (vchiq_ioctl+0x800/0x1968)
[ 5374.954654] [<80600cc4>] (vchiq_ioctl) from [<802835d4>] (do_vfs_ioctl+0xac/0x820)
[ 5374.957308] [<802835d4>] (do_vfs_ioctl) from [<80283d8c>] (SyS_ioctl+0x44/0x6c)
[ 5374.959962] [<80283d8c>] (SyS_ioctl) from [<801080c0>] (ret_fast_syscall+0x0/0x1c)
[ 5374.962624] ---[ end trace d651be8fc8262ca7 ]---
[ 5374.965561] vchiq: vchiq_ioctl: cmd VCHIQ_IOC_RELEASE_SERVICE returned error -1 for service TVNT:9630

To reproduce this error you can download a complete minibian image here:
https://drive.google.com/file/d/0B7wUr-s2z0lNTjZkUWlyUloxUVU/view?usp=sharing
(login root / raspberry)
Tested on pi3 with 2A power supply, and this screen:
https://www.amazon.fr/gp/product/B01FFAAZRC/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

Just plug and unplug hdmi cable...
There is a small video loop starting at boot, but I'm not sure this is related to the issue.
Note that that this issue seems to have no effect, but well... may be this is just a part of an iceberg.

Thank you !

[popcornmix]

I can reproduce. Had a chat with @pelwell and the belief is this is harmless.
It is related to reference counting of vchiq services used by suspend which isn't supported on pi.
The bug appears to be in tvservice which reference counts hdmi attach/detach events.

I'll try to log exactly what is occurring and get a fix, but in the mean time it should be safe to ignore it.

[Aiexis]

OK @popcornmix thank you !
Indeed it's harmless in most cases, but one in thousand times (very approximated of course) it causes omxplayer to freeze. I had this situation this morning at home.

To be more precise, we run about 200 raspberry pi for a in-store network, and everyday we have to reboot one or two of them because omxplayer is freezed. In the same time the load average increases dramaticaly to 4, 5 or even 10 11 if we do nothing. Somethimes a "reboot" command doesn't work and we have to do
echo 1 > /proc/sys/kernel/sysrq ; echo b > /proc/sysrq-trigger
to be able to reboot.
Along with this, while freezed, all tvservice/vcgendcm commands hang

I investigate on this issue for 2 years... tried everything that is in my limited debian knowledge: upgrades/downgrades of raspbian/minibian/omxplayer, changing pi cards, power supply, sd card brand, even hdmi cable...
We can have 90 days without problem, and suddenly 4 reboot needed in the same week (with the same videos).
I can upload a complete image if you want to test, but maybe you will have to wait 3 month...

So, maybe this the issue here is related to the freeze problems but I don't know.
Thanks for your help !

[popcornmix]

Can you try getting this libbcm_host.so and replacing the one in /opt/vc/lib
Does that fix the kernel warning?

[Aiexis]

Warning is still here, even after replacing file and reboot

[ 11.657331] brcmfmac: power management disabled
[ 12.211904] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
[ 12.211958] brcmfmac: power management disabled
[ 12.639176] smsc95xx 1-1.1:1.0 eth0: hardware isn't capable of remote wakeup
[ 12.639402] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 13.076043] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 47.608978] random: crng init done
[ 108.856767] ------------[ cut here ]------------
[ 108.856808] WARNING: CPU: 2 PID: 916 at drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:2501 vchiq_release_internal+0xbc/0x254
[ 108.856819] Modules linked in: brcmfmac brcmutil cfg80211 rfkill bcm2835_gpiomem uio_pdrv_genirq fixed uio snd_bcm2835 snd_pcm snd_timer snd ipv6
[ 108.856893] CPU: 2 PID: 916 Comm: HTV Notify Not tainted 4.9.28-v7+ #998
[ 108.856903] Hardware name: BCM2835
[ 108.856932] [<8010fb3c>] (unwind_backtrace) from [<8010c058>] (show_stack+0x20/0x24)
[ 108.856957] [<8010c058>] (show_stack) from [<804552c0>] (dump_stack+0xd4/0x118)
[ 108.856978] [<804552c0>] (dump_stack) from [<8011d2c4>] (__warn+0xf8/0x110)
[ 108.856998] [<8011d2c4>] (__warn) from [<8011d3ac>] (warn_slowpath_null+0x30/0x38)
[ 108.857017] [<8011d3ac>] (warn_slowpath_null) from [<805ff68c>] (vchiq_release_internal+0xbc/0x254)
[ 108.857037] [<805ff68c>] (vchiq_release_internal) from [<80600340>] (vchiq_ioctl+0x800/0x1968)
[ 108.857058] [<80600340>] (vchiq_ioctl) from [<80283214>] (do_vfs_ioctl+0xac/0x820)
[ 108.857082] [<80283214>] (do_vfs_ioctl) from [<802839cc>] (SyS_ioctl+0x44/0x6c)
[ 108.857104] [<802839cc>] (SyS_ioctl) from [<801080c0>] (ret_fast_syscall+0x0/0x1c)
[ 108.857147] ---[ end trace 7b8b90b64a21086b ]---
[ 108.857186] vchiq: vchiq_ioctl: cmd VCHIQ_IOC_RELEASE_SERVICE returned error -1 for service TVNT:913

[popcornmix]

Yes. Can reproduce (now with raspbian).
I think my testing was unplugging and replugging while video was playing (which works).
The failure comes from unplugging, a new omxplayer starting, and then replugging.

[Aiexis]

I don't notice the same behavior. The failure can occurs while playing a video without changing or stopping it. But the failure never occurs when playing the first video after a reboot. Omxplayer must have stop at least once before there is a problem.
And indeed I had this issue with raspbian since Wheezy.

[Aiexis]

Just a question, is that normal that memory usage rapidly falls down to 10M (and sometimes below) after a few seconds of omxplayer use ?
~# free -htl
total used free shared buffers cached
Mem: 923M 912M 10M 17M 832K 806M
Low: 923M 912M 10M
High: 0B 0B 0B
-/+ buffers/cache: 105M 817M
Swap: 0B 0B 0B
Total: 923M 912M 10M

I have never noticed that (but I have never checked). Maybe it's related to my omxplayer's freezes issues...

[P33M]

http://www.linuxatemyram.com/

This is normal behaviour for any program that does lots of file I/O.

[popcornmix]

Can you test this libbrcm_host.so ?

[Aiexis]

No more message !
Perfect, thank you.
Is there any chance that it also fixes the freeze issue ?

(And thank you @P33M for your answer, sorry I missed it)

[popcornmix]

I think the belief is still that the kernel warning is harmless, so this fix probably won't be related to the freezing.
Check if freezing still occurs and if it does try to find an example that freezes quickly.

[Aiexis]

Freezing just occurs, and dmesg shows thoses messages:

[79869.927589] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[79869.927613]       Not tainted 4.9.28-v7+ #998
[79869.927622] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[79869.927633] HCEC Notify     D    0 18535      1 0x00000005
[79869.927683] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[79869.927705] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[79869.927727] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[79869.927750] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[79869.927773] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[79869.927798] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[79869.927819] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[79869.927842] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[79869.927862] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[79869.927883] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[79869.927901] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[79869.927924] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[79869.927946] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[79869.927967] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[79992.807592] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[79992.807615]       Not tainted 4.9.28-v7+ #998
[79992.807625] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[79992.807635] HCEC Notify     D    0 18535      1 0x00000005
[79992.807686] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[79992.807708] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[79992.807729] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[79992.807753] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[79992.807776] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[79992.807799] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[79992.807820] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[79992.807842] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[79992.807863] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[79992.807883] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[79992.807902] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[79992.807924] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[79992.807947] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[79992.807968] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80115.687598] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80115.687620]       Not tainted 4.9.28-v7+ #998
[80115.687630] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80115.687640] HCEC Notify     D    0 18535      1 0x00000005
[80115.687688] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80115.687709] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80115.687730] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80115.687752] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80115.687775] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80115.687797] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80115.687818] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80115.687839] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80115.687860] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80115.687878] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80115.687897] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80115.687919] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80115.687941] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80115.687962] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80238.567626] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80238.567651]       Not tainted 4.9.28-v7+ #998
[80238.567661] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80238.567672] HCEC Notify     D    0 18535      1 0x00000005
[80238.567723] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80238.567745] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80238.567767] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80238.567791] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80238.567813] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80238.567836] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80238.567857] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80238.567879] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80238.567900] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80238.567919] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80238.567939] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80238.567961] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80238.567983] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80238.568005] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80361.447596] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80361.447620]       Not tainted 4.9.28-v7+ #998
[80361.447630] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80361.447640] HCEC Notify     D    0 18535      1 0x00000005
[80361.447689] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80361.447711] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80361.447732] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80361.447754] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80361.447777] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80361.447800] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80361.447820] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80361.447843] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80361.447864] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80361.447885] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80361.447903] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80361.447925] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80361.447947] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80361.447968] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80484.327609] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80484.327631]       Not tainted 4.9.28-v7+ #998
[80484.327641] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80484.327652] HCEC Notify     D    0 18535      1 0x00000005
[80484.327702] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80484.327724] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80484.327745] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80484.327768] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80484.327792] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80484.327815] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80484.327835] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80484.327857] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80484.327879] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80484.327898] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80484.327917] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80484.327939] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80484.327962] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80484.327983] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80607.207593] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80607.207617]       Not tainted 4.9.28-v7+ #998
[80607.207626] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80607.207637] HCEC Notify     D    0 18535      1 0x00000005
[80607.207687] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80607.207709] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80607.207731] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80607.207755] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80607.207778] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80607.207801] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80607.207822] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80607.207844] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80607.207865] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80607.207885] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80607.207904] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80607.207926] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80607.207948] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80607.207969] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80730.087590] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80730.087611]       Not tainted 4.9.28-v7+ #998
[80730.087620] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80730.087630] HCEC Notify     D    0 18535      1 0x00000005
[80730.087677] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80730.087699] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80730.087719] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80730.087742] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80730.087764] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80730.087787] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80730.087807] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80730.087829] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80730.087849] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80730.087867] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80730.087885] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80730.087907] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80730.087929] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80730.087950] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80852.967593] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80852.967617]       Not tainted 4.9.28-v7+ #998
[80852.967626] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80852.967637] HCEC Notify     D    0 18535      1 0x00000005
[80852.967688] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80852.967711] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80852.967732] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80852.967756] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80852.967778] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80852.967802] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80852.967822] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80852.967844] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80852.967865] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80852.967886] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80852.967905] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80852.967927] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80852.967949] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80852.967969] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)
[80975.847597] INFO: task HCEC Notify:18535 blocked for more than 120 seconds.
[80975.847620]       Not tainted 4.9.28-v7+ #998
[80975.847630] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[80975.847640] HCEC Notify     D    0 18535      1 0x00000005
[80975.847690] [<80713b70>] (__schedule) from [<80714094>] (schedule+0x50/0xa8)
[80975.847712] [<80714094>] (schedule) from [<80717304>] (schedule_timeout+0x220/0x364)
[80975.847733] [<80717304>] (schedule_timeout) from [<80715d48>] (__down+0x88/0xc0)
[80975.847756] [<80715d48>] (__down) from [<8016ace8>] (down+0x54/0x68)
[80975.847780] [<8016ace8>] (down) from [<805ff958>] (vchiq_release+0x134/0x31c)
[80975.847802] [<805ff958>] (vchiq_release) from [<80271d4c>] (__fput+0x9c/0x1e8)
[80975.847823] [<80271d4c>] (__fput) from [<80271f08>] (____fput+0x18/0x1c)
[80975.847845] [<80271f08>] (____fput) from [<8013aad0>] (task_work_run+0xcc/0xfc)
[80975.847866] [<8013aad0>] (task_work_run) from [<801212d4>] (do_exit+0x370/0xaec)
[80975.847887] [<801212d4>] (do_exit) from [<80121ae8>] (do_group_exit+0x4c/0xe4)
[80975.847905] [<80121ae8>] (do_group_exit) from [<8012cb68>] (get_signal+0x370/0x6d4)
[80975.847927] [<8012cb68>] (get_signal) from [<8010b2cc>] (do_signal+0x74/0x3e4)
[80975.847949] [<8010b2cc>] (do_signal) from [<8010b824>] (do_work_pending+0xb8/0xd0)
[80975.847970] [<8010b824>] (do_work_pending) from [<801080e8>] (slow_work_pending+0xc/0x20)

After 22 hours of non-stop video playing.
I have no idea of how to reproduce this quicky...